No sound from Polk external speakers when connected to laptop

the switching of speaker out jack maybe busted. try using headphones if you can hear well then the problem is your Polk external speakers.for the speakers check your other end of the stereo baby phones plug it might not be connected well .if still no sound there might be an electrical and electronic trouble inside your Polk. give a ring on the dealer if still new and still on warranty period, if the warranty lapsed you have no other choice but to open your external speakers, anyway try also to check on color coding of the plug , green is usually the spk out , connect it there, hope this help, thanks for using fixya!